The primary goal of this research is to evaluate client characteristics (comorbidity and family conflict) and treatment processes (barriers to treatment and early participation) as early indicators and predictors of attrition in a school-based open trial of cognitive-behavioral therapy (CBT) for adolescent depression. Rates of depression rise in adolescence, and depressive disorders have been associated with comorbid disorders and detrimental outcomes. While randomized controlled trials (RCTs) provide support for the efficacy of CBT in the treatment of adolescent depression, a substantial portion of depressed adolescents in these trials, and in typical clinical practice, terminate therapy prematurely. Potential contributors to attrition include variations in pre-treatment client characteristics and barriers interfering with treatment attendance and participation. Efficacy trials in university lab clinics apply interventions to a relatively homogeneous recruited sample under controlled conditions which are often not representative of typical clinical practice in community settings. The proposed project complements my training plan in that this investigation will occur within the context of an evidence-based intervention being delivered with components of effectiveness research. This work will identify early markers of attrition which may serve as warning signs that the "usual" delivery of a manualized treatment is not sufficient. These early markers may be useful for both clinicians and investigators as empirically-supported treatments are being evaluated and adapted for dissemination to clinic-referred populations.